Saturday, September 23, 2017

Sun screen: A new threat to a vulnerable reef

Is it our health for theirs? Gili Lankanfushi begins an
eco-sunscreen revolution.

Sun
screen is a holiday essential - from children covered in a thick layer, to the
bald spot on Dad’s head. We think sun screens are safe, but is this the
reality? A key ingredient in more than 3,500 sun protection products is oxybenzone.
This chemical is absorbed into our bloodstream, can cause allergic reactions
and very worryingly was last tested as far back as the 1970’s. It is also
possible that oxybenzone may act similarly to a related chemical, benzophenone which
attacks DNA when illuminated, and can lead to cancer. Studies are currently
being carried out. Annually
four to six thousand tonnes of these chemicals enter our ocean through
wastewater effluent, and by swimmers slathered up with sunscreen. Acting like
an oil slick, the chemicals settle on marine life and the reefs become suffocated.

Reef safe sun screen with no oxybenzone

Corals are animals called polyps that
share their home with algae called zooxanthellae. They work together in a
symbiotic relationship which means both parties benefit. The coral animal
produces a skeleton to shelter the algae whilst building the reef and the algae
through photosynthesis provide the coral animal with 95% of its food. In the
Maldives, the reefs are under severe external pressure. Sun screen is an added
significant hazard which threatens the resiliency of the coral to climate
change.

Healthy coral with blue-green chromis population

Bleaching is the term used when coral loses its symbiotic algae; this can happen for a variety of reasons. A study by R.
Danovaro and a team of scientists showed that oxybenzone promotes latent viral
growth in the symbiotic algae. In the study, fragments of coral were taken
throughout the tropics and incubated with seawater containing small quantities
of sunscreen (10 microlitres). Bleaching occurred within four days, whereas in
the control group which had no sunscreen there was no bleaching. Water samples
taken 18 – 48 hours after sunscreen exposure showed that the symbiotic algae,
instead of being a healthy brown colour were pale/transparent and full of
holes. Additionally viral particles were abundant; 15 times more viral
particles where found in water samples exposed to sunscreen than in the control
group. This suggests that the coral animal or algae contain a latent virus
activated by chemicals in sunscreen. This latent infection is found globally. Oxybenzone
is a photo-toxicant, which means that its negative effects are accelerated by
light - something which the Maldives does not lack. In other studies, oxybenzone
has been found to alter the larval stage of the coral from a healthy swimming
state to a deformed motionless condition. It has also been found to cause DNA
lesions and endocrine disruption, resulting in coral larvae encasing themselves
in their skeletons and dying. The severity of this is proportional to chemical
concentration.

Bleaching experiment by R. Danovaro and his team. They tested the effects of 100-μL sunscreens on Acropora divaricata nubbins after 24-hr incubation at various temperatures. (A) control; (B) nubbins incubated at 28°C; and (C) nubbins incubated (photo credit to R. Danovaro and his team)

In some parts of the world
oxybenzone found on the surface has reached concentrations that indicate the
potential for bio accumulation of this chemical within reef organisms. Since oxybenzone
mimics oestrogen it is causing male fish to change into females. This has been
particularly noticed in turbot and sole feeding near sewage outlets. Since a
healthy fish population is vital for reef survival this feminisation of fish will
have a devastating long term impact.

As the effects of sunscreen are
becoming more apparent positive action is being taken. In Mexico, several
marine reserves have banned the use of none marine safe sun protection products
after high mortality was noted in reef organisms and currently Hawaii is trying
to ban the sale of harmful sunscreen. In addition, the development of
eco-friendly sunscreens is now booming.

We at Gili Lankanfushi want to
become part of this movement and understand that we need to protect our
delicate marine environment, which is why the boutique is now selling a range
of marine safe products, so next time you are here please help us protect our
reef!

Reef safe sun screen that Gili Lankanfushi sells in the Boutique

Please refer to this link for more information and to purchase reef
safe sunscreen.